The SQLite trim() function trims whitespace or other characters from both sides of a string.
The function returns a copy of the string that you provide as an argument, with either whitespace, or other characters as specified, trimmed from both sides.
Continue readingIn SQLite, the rtrim() function enables you to trim whitespace or other characters from the right part of a string.
It returns a copy of the string that you provide as an argument, with the right part trimmed of either whitespace, or other characters as specified.
Continue readingThe SQLite ltrim() function trims whitespace or other characters from the left of a string.
More precisely, it returns a copy of the string that you provide as an argument, with the left part trimmed of either whitespace, or other characters that you specify.
Continue readingThe SQLite like() function enables you to compare a string against a given pattern. You can also specify an escape character if required.
You can use the like() function as an alternative to the LIKE operator (which enables you to run the Y LIKE X [ESCAPE Z] expression).
If you know about the avg() function in SQLite, you’re probably aware that it returns the average of all non-NULL X within a group.
But did you know you can add the DISTINCT keyword to this function?
If you add the DISTINCT keyword, avg() will calculate its results based on distinct values only. This is essentially the same as removing duplicate values and then calculating the average on the remaining values.
In SQLite, the Sum() function accepts an optional DISTINCT keyword that enables you to add just the distinct values in the group. That is, it removes any duplicates from its calculation.
So if there are say, three rows that contain 10, only one of those rows will be included in the results.
Continue readingWhen using the count() function in SQLite, you might find yourself in the situation where you only want to count distinct values. That is, you don’t want duplicate values to be counted multiple times.
SQLite has a function called sum() and another function called total(). Both functions do pretty much the same thing – they return the sum of all non-NULL values in a group.
But there is a subtle difference between these two functions.
The difference is in the way they handle NULL inputs.
Continue readingIn SQLite, the total() function returns the sum of all non-NULL values in a group.
If there are no non-NULL values, then it returns 0.0.
This function is similar to the sum() function, except in the way it handles NULL inputs. When there are no non-NULL values, then sum() returns NULL (instead of 0.0 like the total() function returns).
The SQLite sum() function returns the sum of all non-NULL values in a group.
If there are no non-NULL values, then it returns NULL.
This function basically enables you to add up all the values in a result set or a table.
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